// Copyright 2020 JD.com, Inc. Galileo Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ==============================================================================

#pragma once

namespace galileo {
namespace common {

template <typename T>
class Singleton {
 private:
  static T instance_;
  Singleton() {}

 public:
  static T *GetInstance() { return &instance_; }

  Singleton(const Singleton &) = delete;
  Singleton(Singleton &&) = delete;
  Singleton &operator=(const Singleton &) = delete;
  Singleton &operator=(Singleton &&) = delete;
};

template <typename T>
T Singleton<T>::instance_;

}  // namespace common
}  // namespace galileo
